Consumption meters for measuring consumption data of a supplied utility, for example electricity meters, heat meters for district heating, and water meters for cold or hot water, are often equipped with a communication unit for remote communication with the meter. Remote communication greatly facilitates data collection and different collection schemes for collecting the data exist.
In one type of collection scheme, a mobile collector system is used. In such a system short range data messages are transmitted from the meter, or from a communication device attached to the meter, to a collector unit moved by the transmitter device to collect the transmitted data, normally either by passing by with a vehicle or simply walking by (drive-by/walk-by collection). In such a system meter data can be collected without a need to enter the property of the customers, a person or a vehicle only needs to pass by within the communication range of the transmitted signal. Mobile collector systems may be kept simple and inexpensive.
In another type of collection scheme, fixed collectors are used. In such a system a communication network is constructed so that data are transmitted from the meter to the utility or other data collector station in a fully automated manner. The advantage of such a system is that data can be collected automatically and thereby with short fixed intervals if desired. However, the installation and maintenance of such a system renders it more expensive than a mobile collector system, and often a rather large number of meter sites is needed within an area in order to justify the cost.
In some cases mobile and fixed collector systems are combined in a so-called dual transmission system. In a dual transmission system, different data messages are sent by the transmitter to be collected by (at least) two different types of receiver devices. Dual transmission systems may e.g. be desired in order to provide a backup route of data to the data collector station.    A number of dual transmission systems is disclosed with the prior art. In U.S. Pat. No. 7,626,511 a dual transmission system is disclosed where a meter is arranged for transmitting a plurality of narrow band signals at a limited power level and a plurality of frequency-hopping, spread-spectrum signals at a high power level. The narrow band signals are transmitted at intervals which are shorter than the spread-spectrum signals. In this solution, distinct signals are used for different receiver devices.